GIBRALTAR ISLAND – Despite toxic algae fouling Toledo's drinking water in early August, Lake Erie harmful algae still is much less severe than the record-setting 2011 algal bloom, a scientist said Monday.

And the algae shouldn't be near as bad as 2013, either, said Rich Stumpf, National Oceanic and Atmospheric Administration harmful algal bloom coordinator and oceanographer.

Stumpf stood by scientists' July 10 forecast that predicted the bloom likely will be a six on a scale of one to 10, with one being the best and 10 being the worst. The 2011 bloom, which stretched into the lake's Central Basin toward Cleveland, is considered a 10.

The bloom also should not be as bad as last year, which also was less severe than 2011, he said. The forecast is for Lake Erie's Western Basin, which stretches from Toledo to Sandusky, and not the entire lake.

"Unfortunately, it is a significant bloom," said Stumpf, who spoke to journalists via conference call Monday at Ohio State University's Stone Laboratory on Gibraltar Island. "Ask anyone in Toledo."

Toxic algae — which is really a bacteria called microcystis — can produce a toxin that can cause gastrointestinal illness and liver problems. In early August, Toledo issued a do-not-drink advisory to its more than 400,000 water customers in Northwest Ohio and southeast Michigan because the toxin, called microcystin, had contaminated the water.

There are no state or federal requirements for testing for the toxin or treating it, and normal water treatment processes do not remove it. Boiling water doesn't remove the toxin, either.

The World Health Organization recommends drinking water have no more than 1 part per billion of microcystin. During its water crisis, Toledo's water had 5 parts per billion, said Justin Chaffin, senior researcher and research coordinator for Stone Lab and Ohio State University's Ohio Sea Grant College Program.

In September, Carroll Township's water plant couldn't provide drinking water to residents for three days. Its level of toxin was 3.5 parts per billion, Chaffin said. Carroll Township is east of Toledo on Lake Erie.

Toledo ran into problems likely because northerly winds pushed the algae up to Toledo and around its water intake, causing a thick bloom to mix into the water column and get pulled into the plant, Stumpf said. The algae, which started blooming as it normally does in late July, grew rapidly, contributing to the problem, he said.

"The location depends on the wind," Stumpf said.

Satellite images from Aug. 3 shows the bloom was very thick around Toledo, but a few days later, it had moved southeast and stretched further along the Lake Erie shore.

Northerly winds will continue to send it to the Ohio shore, and a southerly wind will push it up toward Canada, he said.

Harmful algae was a problem on Lake Erie in the 1960s and '70s, then re-emerged as an issue in 2002. Phosphorous runoff fuels the blooms, and it comes mostly from fertilizer runoff. Other sources, such as sewer plants, contribute.

NOAA has worked with The Ohio State University and Heidelberg University to put out an algae forecast each July since 2012.

This year, scientists decided to revisit their forecast in August because they underestimated the severity of the 2013 bloom. They found the amount of rain in July can be a factor in how bad the algae will be because a rainy July could add to the amount of phosphorous getting into the lake.

The amount of phosphorous loading this July was small, leading Stumpf to believe the forecast likely will be on target.

The bloom will get worse and likely peak in September, which is when it usually is worst, Stumpf said.

mksmith@gannett.com

419-734-7521

Twitter: @kristinasmithNM

Toxic algae

• After the Toledo water crisis, the National Oceanic and Atmospheric Administration began issuing its weekly harmful algal bloom bulletin twice a week. The bulletin includes satellite images of the bloom and allows people to see where the bloom is located at a given time. The bulletin can be found here: http://www2.nccos.noaa.gov/coast/lakeerie/bulletin/bulletin_2014-013.pdf.

• There are no advisories related to harmful algal blooms at state park beaches in Ottawa County.